The purpose of the work is to define the steroid hormone environment of normal aged and neoplastic sex accessory tissue. To this end, the endogenous concentrations of various androgens, the activity of intracellular steroid hormone reductases and dehydrogenases, and the activity of specific intracellular androphilles will be determined. To define the hormonal environment of aged animals, guinea pigs and rats will be utilized. Dogs will be used to provide hyperplastic prostate glands. This work will also concentrate on comparing and contrasting the epithelium and stroma of the different glands. BIBLIOGRAPHIC REFERENCES: Mawhinney, M.G., and Belis, J.A.: Androgens and Estrogens in Prostatic Neoplasia (Submitted for Publication - Review article) in Recent Advances in Sex Hormone Res. Vol. II Thomas and Singhal ed. 1976. Mawhinney, M.G., Schwartz, F.L., Robinette, C.L., Nunnery, W.E., Belis, J.A. and Milam, D.F.: Androgen and Estrogen dynamics in the male -(Exhibit) Americal Urological Assn. Proc., 1975.